“Solid state fermentation for the production of alkaline protease by Bacillus cereus 1173900 using proteinaceous tannery solid waste.

Current science (Impact Factor: 0.83). 01/2011; 100:726-730.

ABSTRACT Animal fleshing, the major proteinaceous solid waste
generated from leather industry, was used as substrate
for the production of alkaline protease by Bacillus
cereus 1173900 in solid-state fermentation (SSF).
Maximum protease activity of 12,310 U/g was observed
at 60 h in SSF crude extract. The extracted
protease enzyme was purified by 53.64-fold through
ammonium sulphate precipitation and chromatography
separation in Sephadex G-100. The purified protease
had a specific activity of 201.6 (U/mg). The molecular
weight of the purified enzyme was 66 kDa, determined
by SDS–PAGE. The zymogram also revealed a clear
hydrolytic zone due to proteolytic activity, which
coincided with the band obtained with SDS–PAGE.
Enzyme activity was inhibited by EDTA, suggesting
that the enzyme belongs to metalloprotease(s).

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